eCircuit Center – Spice Schematics

“The goal is a site where the learning of electronics is hands-on and fun. And the SPICE circuit simulator is a great software tool to achieve that goal. It hit me the first time I used SPICE – simulating is fun! And because it’s easy to use, I’ve spent a lot of time building and exploring circuits.” – Rick

eCircuit Center – Spice Schematics

SPICE is capable of performing both AC (frequency) Analysis and Transient (time) Analysis. SPICE also performs a number of other analyses like DC, Sensitivity, Noise and Distortion.

SPICE Basics, SPICE Commands, Circuit Collection

eCircuit Center - Spice Schematics

“At the core of the function generator is a triangle wave generator. How do you generate a triangle wave? The most common way is to get a capacitor and then alternate charging it and discharging it. But how to you get a nice linear ramp across the capacitor?”

Triangle and Square-Wave Generator

Simulation Circuit Examples –

  • Programmable Gain Amplifier (PGA) Op Amp
  • Single-Supply AC Inverting Amplifier
  • Instrumentation Amp (3 Op Amp)
  • Sensor Bridge with Current Bias
  • The PID Controller
  • Pulse Width Modulation
  • Precision Half-Wave Rectifier

Usability and Accessibility Enhancements

Tablets have tools for Communication, Browsing and Many Utilities. It needs to be usable by very old people and very young ones as well.  They need to be affordable and Robust too. Ability to survive falls, Grime, Water and Heat. It should be usable by people having Health issues too.

Usability and Accessibility Enhancements

Alert sounds likes chimes and rings are not enough, The Tablet must be able to yell and scream when it is far from the owner. The user needs to wear  a Bluetooth pendent with microphone .

When charge is low, it has to create a tantrum till it is fed…up. Some pricey models can have tiny wheels to move to the closest charging bunk. Some Vacuum Cleaners are able to move and recharge themselves.

When a SMS lands, it is able to read out loud and take a reply by voice and send it at once. Similarly the email could work on the tablets, all hands-free. The speakers and quality audio are on the tablet/pad and the pendent is just an additional microphone with bluetooth and vibrator with a titillate option.

Incoming  calls can move in tandem with an answering device and make loud Audio Visual Effects to get the attention of the Owner. The caller cannot wait, so the answering machine takes the call, says “please wait” and then rings the Alert Alarm Bells and even vibrates the Pendent. The Senior now can talk to the pendent and will get the caller’s voice loud on the Phone. The Phone Audio has to be very good and loud.

If the room has a connected HD Monitor, even that can be used for the communication purpose. The user just needs to click the pendent to answer a call or video chat with family friends. In Business too, Large monitors and Loud Speakers can improve communication.

Smart PowerPacks or PowerBanks+ can be the Charging Stations. The Power Packs with docks can have the wheels and intelligence to recharge the device on alert, they will also recharge themselves from the mains power, whenever required.

Expensive Phone or PowerPack Models can have Drone Mode. I say this emphatically because the Dilbert Dupey develops wings after the mutation, This indicates that quad-copters, drones were predicted. It could be that, One fine Day the Tablet+ may Fly!

Aug 2014 – delabs Technologies

Wireless Handheld Multimedia Computers

The Average home user or a majority of mankind have trouble even when operating a TV remote control. Things are not as simple as a Water Tap or a Toggle Switch. An Easy to use Handheld is more important than any technology or features that may be available for that. Ergonomics, Utility or Application, Quality and Cost are the basic requirements of the consumer.

Wireless Handheld Multimedia Computers

A Handheld gadget for the masses, needs to be a Entertainer and Communicator. It has to be wireless and should at least get into a Coat Inner pocket or Small Bag. It is a Duarble Consumer Electronics Product, comparable to the first Popular Tape Recorders from Philips or Grundig.

Wireless Gigabit Alliance – WiGig 60 GHz

Wifi and WiMax are the things that are being talked-blogged about and being tried. I just got some idea about these technologies and have my feedback or understanding.

If Somebody asked me to set up a low cost wifi connectivity in a small housing complex, I would just strap a wireless router on the pole on every street corner, the poles or junctions being the ones used for existing cable broadband. Then depending on subscriptions and demand, improve the capacity of the network within the budget of the colony.

The handheld can have simultaneous connection to two or three routers and as the person moves, drop a weak path and take up a new router which is strong. This is just my hunch.

The Handheld could be used for three types of wireless connections.

Full Multimedia Duplex – Like Video Telephone, WebApps – 100 units money charge per hour.

Semi Multimedia Duplex – Like Interactive Quiz, Games – Up is Text, Down is Video – 50 Units /hr.


Multimedia Broadcast – Digital Radio Podcast, TV Show Podcast, Movie Podcast – 15 Units/hr.

The TV and Radio Shows on subscribed podcasts can be downloaded and stored when it is transmitted live; but seen any time, any number of times, but transmitted only once. This is a wireless Transmission with an advance program xml feed info. It is just like Regular TV. This is to avoid bandwidth wastage on multiple downloads of same show by the people in one block. Even software updates and games can be brodcast and stored in background.

The usage of Internet and phone remains duplex and will take more resources. The handheld usage for entertainment may be very high. Duplex for that will cause excess costly load. Normal usage of Internet for browsing, mail and webapps may become difficult as more entertainment load builds. Entertainment on Handheld is best as a one time brodcast with a advance feed.

Drawing Tools for Electronic Schematics in Android

Conclusion – Wireless Handhelds connectivity must have separate interfaces for Web and Media. The Web is the same as Lan Wifi but Movies and Games can be connected by a Broadcast Show. And seen on Handheld by wireless Programmable Live Reception with storage.

delabs around 07-08 – First in Nomadic Computing

Wireless Home Automation and Application Server

The PC has much Evolved, From XT to AT, then from 286 to 586, the evolutionary trend continues. The Speed: GHz, Space: GB and Software: Linux-XP, have grown rapidly. The other vital things Interface, Networking and Power Consumption moved a bit slower. So some suggestions on the New Desktop for Small Office and Home Standard, that is crucial in the present computing scenario.

Enterprise Level Hardware and Software can be extrapolated from this idea for a SOHO. An Enterprise is like a SOHO Cluster. One big Homogeneous Entity is unstable and unreliable. When small varied, self-dependent entities collaborate to form an Enterprise, it is a Cluster of SOHOs, which is a Reliable and Resilient Entity.

Wireless Home Automation and Application Server

A Green solution could be New Desktop Computing Standard – The quiescent losses in this is only the wifi server cube, which can serve 6 tablets or UMPC. So if 6-12 people are using computers, many desktops need not be on. Tablets, Laptops and Notebooks consume less power and run on batteries. Thin Custom Notebook and Tablet Clients can use one OpenOffice on the WiFi Application Server cube

Nomadic Computing – WebOS – 2004

Nomadic Computing - WebOS

SOHO Desktop Standard

  • The Desktop Home Computer is the Wireless Router, Power Server.
  • SMPS Power Supply runs Both on 230V-110V AC and 12-24 V DC.
  • Home Wifi Computer, Application and Web Server is just a Cube.
  • Wireless Networked Peripherals, Printers, Drives, Viewers, Inputs.
  • Desktop Wifi Server networks 6 Handhelds and 12 peripherals.
  • Wireless Ethernet LCD Monitor-Keyboard for System Admin.
First posted in 2006 – delabs